The Alpha (Pohatcong) Grasslands is a historic farming area situated between the Delaware River and the Boroughs of Alpha and Phillipsburg in southwestern Warren County. The site consists predominately of open fields ranging from pasture and mixed use agriculture to grassland and fallow fields. The Alpha Grasslands is a Natural Heritage Priority Site with approximately 1000 acres preserved as open space and farmland through New Jersey Department of Environmental Protection?s (NJDEP) Green Acres Program. This site is located within the Highlands Preservation Area, a region of exceptional natural resource value designated by NJDEP?s Highlands Water Protection and Planning Act (Highlands Act).

Ornithological Summary

Conservation Concern ? State-endangered: Vesper Sparrow (B)

Conservation Concern- State-threatened: Savannah Sparrow (B)

Conservation Issues

The construction of Interstate 78 in the late 1980s permanently fragmented the Alpha Grasslands. Grasslands north of Interstate 78 have since succumbed to development. The southern portion is largely undeveloped and contiguous; however, it remains vulnerable to development as unprotected land and is impacted by the high density development north of Interstate 78. Any changes in farming practices could also be detrimental to grassland bird populations. Protection and restoration of these parcels is recommended through acquisition, enrollment in NJ?s Farmland Preservation Program or through participation in conservation incentive programs. Outreach to landowners should promote implementation of a variety of grassland management techniques, including delayed mowing and haying, grazing and prescribed burning. Landowners should be encouraged to delay mowing until mid-June to allow young birds sufficient time to fledge. Habitat management may also include the creation of buffers, filter strips and native warm season grasslands. Grassland restoration and enhancement is a priority for several federal and state incentive programs that fund habitat improvement projects on private lands. The Natural Resource Conservation Service?s Wildlife Habitat Incentives Program, for example, has funded a native warm season grassland restoration at the Alpha Grasslands. Organizations actively pursuing protection of these valuable grasslands include The Phillipsburg Riverview Organization, Delaware and Raritan Greenway and NJDEP?s Green Acres Program. Local community members have also successfully advocated for the protection of this area. Additional threats include overabundant deer and invasive plant species.


The site is held by various private landowners.


Grasslands, pastures, agricultural fields and fallow fields

Land Use

The site contains large amounts of pasture (dairy and horses), cornfields, and fallow fields. There is also some redidential development and a small amount of forestry occurring.

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